1. Field of the Invention
The present invention relates generally to firearms adapted to be mounted with a scope. More specifically, the present invention concerns an improved scope-mounting base including an adjustable recoil lug for preventing undesired movement of the base relative to the firearm when the firearm is fired. Additionally, the improved scope-mounting base enables a secure and level mounting on virtually any type of firearm. The improved base of the present invention also includes improved ring clamps that enable uniform and optimized torque applied between the ring clamps and the mount.
2. Discussion of Prior Art
It is desirable to utilize a scope to facilitate aiming a firearm in many shooting applications, particularly long-range target shooting using high-powered firearms and large caliber ammunition. Conventional scopes are typically mounted onto the firearm after market and enable a user to focus and magnify a target in the line of sight at distances well in excess of one-thousand yards. These scopes further allow the user to finely adjust the sighting provided by the scope to precisely match the particular firearm and the specific application. However, when the firearm is fired, significant recoil forces act on the firearm, as well as the scope mounted thereon. Accordingly, it is desirable to mount the scope to the firearm in a secure manner. It is further desirable to provide a mount that enables securement in a cost-effective manner that can be easily accomplished by the user after market, for a wide variety of scopes and firearms.
Scope bases for securing a scope to a firearm are known in the art. These prior art bases include a mount that is secured to the receiver of the firearm and adjustable ring clamps that clamp the scope to the mount. Prior art mounts typically are secured to the receiver of the firearm with a plurality of screws (e.g., many firearms come pre-drilled with 3,4 or 5 threaded holes in the top of the receiver). With these prior art bases, the recoil forces often undesirably cause the scope to loose its sight adjustment, become loosened, or in extreme cases shear off of the firearm. These problems are exacerbated when the scope is not tightly secured to the mount. While prior art bases attempt to secure the scope to the mount, they are deficient in most cases and typically achieve a loose, or xe2x80x9cspongyxe2x80x9d coupling between the scope and the mount.
For example, most prior art ring clamps utilize a movable jaw having flat, angled surfaces (e.g., forty-five degrees, etc.) that engage a weaver-style, cammed mount with complemental angled surfaces. The movable jaw is compressed by engaging the flat surface of a screw with a flat backside of the jaw. If everything is perfectly fit and centered, the moveable jaw creates a correct torque factor with the mount, i.e. a torque factor that evenly centers the clamping force over the center of the mount and securely couples the scope to the mount. However, as is most often and undesirably the case, when the jaw does not perfectly engage the mount (e.g., when the mount or jaw surfaces are not uniform, etc.), the torque is applied too high on the ring and an undesirable spongy connection is created between the scope and the mount, rendering recoil forces all the more likely to undesirably alter or damage the scope. Additionally, prior art mounts utilize an arcuate undersurface that roughly matches the arcuate top circumference of the receiver of the firearm. If the arcuate surfaces exactly match, the surfaces correctly marry and the mount is centered over the receiver. However, as is more often the case, where the arcuate surfaces do not match (e.g., where the receiver has been belt-sanded, etc.), the mount typically does not center over the receiver. It is known in the art to utilize an epoxy between the mount and the receiver to help alleviate this problem and to add to the mounting force. However, the mismatched arcuate surfaces are undesirable in this regard in that there is insufficient space for the epoxy and thus the epoxy tends to worsen the problem with securely centering the mount over the firearm receiver.
It is also known in the art to machine a xe2x80x9cstepxe2x80x9d integral with the bridge of a weaver-style base mount that extends into the ejection port of the firearm and engages one or both of the faces thereof to assist in preventing the harmful effects of the recoil forces on the scope. These stepped bridges, however, are problematic and subject to several limitations. For example, the machined steps are difficult and costly to manufacture. In addition, each stepped mount must be custom made to fit the particular firearm it is mounted on because cartridge ejection ports are typically not uniform or consistent from firearm to firearm.
The present invention provides an improved scope-mounting base that does not suffer from the problems and limitations of the prior art bases detailed above. The inventive base includes an adjustable recoil lug for preventing undesired movement of the base relative to the firearm when the firearm is fired. The adjustability of the recoil lug enables the lug to be used on virtually any firearm having an ejection port without the need to specially manufacture the lug for the particular firearm. In a preferred embodiment, the mount includes a recessed groove operable to receive epoxy that enables a secure and level mounting on virtually any type of firearm. In a preferred embodiment, the improved base of the present invention also includes improved ring clamps including arcuate engagement surfaces that enable a consistently uniform and optimized torque applied between the ring clamps and the mount.
A first aspect of the present invention concerns a base for mounting a scope on a firearm wherein the firearm includes a cartridge ejection port presenting a front face and a rear face. The base broadly includes a mount adapted to be mounted on the firearm and a lug adjustably coupled to the mount. The mount includes a bridge section extending over the ejection port when the mount is mounted on the firearm. The lug projects out of the bridge section. The lug presents an engagement surface extending below the bridge section and being shiftable relative to the mount. The engagement surface is shiftable into engagement with one of the faces of the ejection port when the mount is mounted on the firearm to prevent movement of the mount relative to the firearm when the firearm is fired.
A second aspect of the present invention concerns a firearm broadly including a receiver presenting an elongated hollow chamber defining a longitudinal axis, hardware associated with the receiver and operable to fire ammunition out of a barrel coupled to the receiver, a base mounted on the receiver, a lug adjustably coupled to the base, and a scope removably coupled to the base. The receiver includes a cartridge ejection port presenting a front face and an oppositely spaced rear face. The front and rear faces are generally perpendicular to the longitudinal axis. The base is mounted on the receiver above the ejection port and includes a bridge section extending over the ejection port. The lug projects out of the bridge section and presents an engagement surface extending below the bridge section and being shiftable relative to the base. The engagement surface is shiftable into engagement with one of the faces of the ejection port to prevent movement of the base relative to the firearm when the firearm is fired.
A third aspect of the present invention concerns a base for mounting a scope on a firearm and broadly includes a mount adapted to be mounted on the firearm and at least one ring clamp adjustably coupled to the mount and operable to clamp the scope to the mount. The ring clamp includes a housing, a first jaw fixed relative to the housing, and an opposed second jaw spaced from the first jaw. The second jaw is shiftable relative to the first jaw and presents a first, a second, and a third engagement surface. The ring clamp further includes a headed fastener rotatably supported relative to the housing. At least a portion of the fastener engages the first engagement surface to cause the second jaw to shift into an engagement position wherein the second engagement surface engages the housing and the third engagement surface engages the mount. At least one of the first, second and third engagement surfaces is arcuate.